# Why quantum computing companies use superconducting qubits? [closed]

Why are superconducting qubits superior to other types of experimental realisation of qubits? I assume this because Dwave, IBM, rigetti among other companies in the quantum computing business use superconducting qubits.

• This would be a good question for SE.QuantumComputing. – Nat May 9 '18 at 21:02
• Not all do. See e.g. Xanadu, aimed at optical quantum computing, or Microsoft research, striving to realize topological quantum computation – glS May 10 '18 at 7:34

The time scale $\tau$ scale for decoherence usually goes like some power of the temperature $T$. E.g., for a free electron undergoing Thomson scattering by blackbody radiation, $\tau\propto T^{-5}$. This suggests that you want the temperature as low as possible. In general, an ultra-low-temperature electronic device is probably going to be superconducting, both because nonzero resistance would create heat and because many materials happen to become superconducting at very low temperatures.